The temperature on September 20, 1915 was between 2.9 °C and 16.6 °C and averaged 10.4 °C. There was 10.8 hours of sunshine (87%). The average windspeed was 3 Bft (moderate breeze) and was prevailing from the northeast. Source: KNMI
In The Netherlands , there was from August 29, 1913 to September 9, 1918 the cabinet Cort van der Linden, with Mr. P.W.A. Cort van der Linden (liberaal) as prime minister.
January 25 » Alexander Graham Bell inaugurates U.S. transcontinental telephone service, speaking from New York to Thomas Watson in San Francisco.
May 7 » World War I: German submarine U-20 sinks RMS Lusitania, killing 1,198 people, including 128 Americans. Public reaction to the sinking turns many former pro-Germans in the United States against the German Empire.
July 24 » The passenger ship SSEastland capsizes while tied to a dock in the Chicago River. A total of 844 passengers and crew are killed in the largest loss of life disaster from a single shipwreck on the Great Lakes.
August 4 » World War I: The German 12th Army occupies Warsaw during the Gorlice–Tarnów Offensive and the Great Retreat of 1915.
September 12 » French soldiers rescue over 4,000 Armenian Genocide survivors stranded on Musa Dagh.
November 25 » Albert Einstein presents the field equations of general relativity to the Prussian Academy of Sciences.
Day of marriage February 14, 1940
The temperature on February 14, 1940 was between -16.5 °C and -4.3 °C and averaged -8.8 °C. There was 0.7 mm of rain during 4.4 hours. The average windspeed was 4 Bft (moderate breeze) and was prevailing from the north. Source: KNMI
In The Netherlands , there was from August 10, 1939 to September 3, 1940 the cabinet De Geer II, with Jonkheer mr. D.J. de Geer (CHU) as prime minister.
In The Netherlands , there was from September 3, 1940 to July 27, 1941 the cabinet Gerbrandy I, with Prof. dr. P.S. Gerbrandy (ARP) as prime minister.
January 29 » Three trains on the Nishinari Line; present Sakurajima Line, in Osaka, Japan, collide and explode while approaching Ajikawaguchi Station. One hundred and eighty-one people are killed.
May 5 » World War II: Norwegian Campaign: Norwegian squads in Hegra Fortress and Vinjesvingen capitulate to German forces after all other Norwegian forces in southern Norway had laid down their arms.
June 3 » Franz Rademacher proposes plans to make Madagascar the "Jewish homeland", an idea that had first been considered by 19th century journalist Theodor Herzl.
October 7 » World War II: The McCollum memo proposes bringing the United States into the war in Europe by provoking the Japanese to attack the United States.
November 24 » World War II: The First Slovak Republic becomes a signatory to the Tripartite Pact, officially joining the Axis powers.
December 14 » Plutonium (specifically Pu-238) is first isolated at Berkeley, California.
Day of death October 13, 1971
The temperature on October 13, 1971 was between 6.8 °C and 12.0 °C and averaged 9.5 °C. There was 3.4 mm of rain during 7.4 hours. The almost completely overcast was. The average windspeed was 3 Bft (moderate breeze) and was prevailing from the northeast. Source: KNMI
January 22 » The Singapore Declaration, one of the two most important documents to the uncodified constitution of the Commonwealth of Nations, is issued.
January 25 » Charles Manson and three female "Family" members are found guilty of the 1969 Tate–LaBianca murders.
February 9 » Satchel Paige becomes the first Negro League player to be voted into the USA's Baseball Hall of Fame.
May 3 » Erich Honecker becomes First Secretary of the Socialist Unity Party of Germany, remaining in power until 1989.
October 27 » The Democratic Republic of the Congo is renamed Zaire.
November 6 » The United States Atomic Energy Commission tests the largest U.S. underground hydrogen bomb, code-named Cannikin, on Amchitka Island in the Aleutians.
When copying data from this family tree, please include a reference to the origin: Joop Klavers, "Family tree Klavers", database, Genealogy Online (https://www.genealogieonline.nl/stamboom_klavers/I537366.php : accessed January 25, 2026), "Harm Holwerda (1915-1971)".
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